1. Field of the Invention
The present invention relates generally to a handheld tool, and more particularly to an innovative one which is configured with a connecting rod for the tool head.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
The common electric screwdrivers with adjustable assembly heads permit assembly or replacement of screwdriver heads or drill heads of different sizes. However, owing to larger external diameter, said assembly head cannot be inserted into a small gap wherein the screws are located. Hence, a connecting rod of a tool head has been developed for this purpose. As for said connecting rod of tool head, one end is generally provided with an assembly rod adapted onto the assembly head of the electric screwdriver, and the other end is extended to a preset length and provided with a tool head slot for the screwdriver heads or drill heads.
Said connecting rod of tool head is structurally configured in such a manner that an elastic release mechanism is generally set to make the screwdriver head generate a springing action for easily taking out the tool head. According to the conventional configuration of said elastic release mechanism, a control loop is arranged onto the periphery of the inserting end of the screwdriver head for the tool head connecting rod. By pushing the control loop, the locating member preset in the connecting rod of the screwdriver head can be controlled into a release state, so that the inserted tool head can spring out to a certain distance, allowing for easily taking out by the user. Yet, it is observed from actual applications that, as the control loop is arranged onto the periphery of the inserting end of the tool head connecting rod, the external diameter of the tool head connecting rod is expanded, so it cannot be inserted into small gap without expected functions and advantages.
Moreover, said control loop is operated manually by gripping and pushing with at least two fingers (generally thumb and forefinger), this makes it inconvenient and difficult to hold manually and apply a force to it.
Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
Therefore, the inventor has provided the present invention of practicability after deliberate experimentation and evaluation based on years of experience in the production and development of related products.